Example Questions

Example Question #1 : Understanding Carbohydrates

Which of the following is one of the primary functions of carbohydrates?

Possible Answers:

Catalyze chemical reactions

Energy storage

Protect cell organelles

Maintain genetic fidelity

Correct answer:

Energy storage

Explanation:

Carbohydrates, such as glucose and fructose, are primarily used in metabolic pathways to provide energy for the cell. Glucose is the first reactant necessary for driving glycolysis and subsequent cellular respiration in the cell, with the goal of producing ATP.

Example Question #2 : Understanding Carbohydrates

Which of the following is a carbohydrate?

Possible Answers:

Mannose

Lipase

miRNA

Cholesterol

Correct answer:

Mannose

Explanation:

Mannose is an epimer of glucose, and is a carbohydrate. Typically, molecule names ending in "–ose" will be carbohydrates. The other answers each belong to a different category of macromolecule: cholesterol is a lipid, miRNA is a nucleic acid, and lipase is a protein.

Just as the suffix "ose" signifies a carbohydrate, the suffix "ol" indicates a lipid and the suffix "ase" indicates a protein.

Example Question #1 : Understanding Carbohydrates

Which of the following carbohydrates does not have a molecular formula of ?

Possible Answers:

Glucose

Galactose

Mannose

Ribose

Correct answer:

Ribose

Explanation:

Carbohydrates have an empirical formula of . The most common types of carbohydrates are pentoses (5-carbon carbohydrates) and hexoses (6-carbon carbohydrates). All 6-carbon carbohydrates share the molecular formula .

Glucose, galactose, and mannose are all hexoses. The only difference between these three carbohydrates is their relative orientation of hydroxyl groups on the carbons.

Ribose is a pentose, and has a different molecular formula. Remember that all nucleic acids contain 5-carbon rings.

Example Question #5 : Understanding Carbohydrates

Increased levels of insulin will increase the amount of glycogen stored in the pancreas

Decreased levels of insulin promotes breakdown of glycogen into galactose

Increased levels of insulin will increase the amount of glycogen stored in the liver

Decreased levels of glucagon promotes breakdown of glycogen into galactose

Correct answer:

Increased levels of insulin will increase the amount of glycogen stored in the liver

Explanation:

Recall that glucagon promotes the breakdown of glycogen to glucose, whereas insulin promotes formation of glycogen from glucose molecules. Both hormones function to regulate glucose levels. You can eliminate choices with galactose because glycogen is made up of glucose, not galactose.

You can also eliminate the answer choice that suggests that glycogen is stored in the pancreas. The pancreas releases the hormones insulin and glucagon, but it doesn’t store glycogen. The glycogen is actually stored in the liver. Increased levels of insulin increase the amount of glycogen stored in the liver.

Example Question #6 : Understanding Carbohydrates

What is the main source of carbohydrates used in the human body for energy?

Possible Answers:

Sucrose

Lactose

Glucose

Fructose

Galactose

Correct answer:

Glucose

Explanation:

Glucose is the main source of energy in the human body. It is a six carbon sugar that, when fully oxidized, can yield as many as 36 ATP. The brain in the human body uses glucose exclusively, though other parts of the body are capable of metabolizing other sugars. When complex sugars are ingested, they are broken down and converted by various enzymes to produce glucose. The glucose then enters into glycolysis to generate cellular energy.

Glycolysis occurs within the cytosol of the cell, during both aerobic and anaerobic respiration. Glycolysis is the first step to generate energy from the breakdown of carbohydrates.

Glycolysis does not involve the breakdown of proteins or fatty acids. Fermentation can be used to regenerate NAD+, with a byproduct of lactic acid or ethanol, during anaerobic respiration. Glycolysis will occur simultaneous to fermentation, but will also occur during healthy aerobic respiration.

Example Question #1 : Understanding Carbohydrates

Which of the following is not a basic biological building block?

Possible Answers:

Nucleotide

Monosaccharide

Enzyme

Amino acid

Fatty acid

Correct answer:

Enzyme

Explanation:

Enzymes are proteins, which are composed of amino acids. Biomolecules are made of polymers. The monomers in nucleic acids are nucleotides. The monomers in carbohydrates are monosaccharides. Lipids are biomolecules, but their structure does not follow as clear of a pattern as the other three. Depending on the textbook, we may consider fatty acids, or hydrocarbons as "monomers" of lipids. There is some ambiguity with lipids because their structures are diverse and are not always chains of repeating subunits.

Example Question #2 : Understanding Carbohydrates

Which of the following is a polymer composed of sugar monomers?

Possible Answers:

Carbohydrates

Lactose

Glucose

Proteins

Lipids

Correct answer:

Carbohydrates

Explanation:

Carbohydrates and proteins are polymers (a long chain molecule generally composed of repeating single units), but glucose and lipids are not polymers (though glucose has the ability to polymerize). Proteins are polymers of amino acids. Carbohydrates are polymers of sugar monomers or monosaccharides. Lactose is a disaccharide or two sugar monomers connected.

Example Question #3 : Understanding Carbohydrates

Which of the following terms is defined as the process by which water breaks polymers down into monomers?

Possible Answers:

Hydrolysis

Condensation synthesis reaction

Anabolic reaction

None of these

Correct answer:

Hydrolysis

Explanation:

Polymers are broken down into monomers via hydrolysis. Hydrolysis is the reverse of a condensation synthesis reaction. In hydrolysis, adding water molecules breaks the bonds between monomers. In this reaction polymers are broken down when the hydrogen of the water molecules attaches to one monomer and the hydroxyl attaches the next monomer.

All AP Biology Resources

Report an issue with this question

If you've found an issue with this question, please let us know. With the help of the community we can continue to
improve our educational resources.

Do not fill in this field

* Your Name:

* Your Email:

* Issue Description:

DMCA Complaint

If you believe that content available by means of the Website (as defined in our Terms of Service) infringes one
or more of your copyrights, please notify us by providing a written notice (“Infringement Notice”) containing
the
information described below to the designated agent listed below. If Varsity Tutors takes action in response to
an
Infringement Notice, it will make a good faith attempt to contact the party that made such content available by
means of the most recent email address, if any, provided by such party to Varsity Tutors.

Your Infringement Notice may be forwarded to the party that made the content available or to third parties such
as
ChillingEffects.org.

Please be advised that you will be liable for damages (including costs and attorneys’ fees) if you materially
misrepresent that a product or activity is infringing your copyrights. Thus, if you are not sure content located
on or linked-to by the Website infringes your copyright, you should consider first contacting an attorney.

Please follow these steps to file a notice:

You must include the following:

A physical or electronic signature of the copyright owner or a person authorized to act on their behalf;
An identification of the copyright claimed to have been infringed;
A description of the nature and exact location of the content that you claim to infringe your copyright, in \
sufficient detail to permit Varsity Tutors to find and positively identify that content; for example we require
a
link to the specific question (not just the name of the question) that contains the content and a description of
which specific portion of the question – an image, a link, the text, etc – your complaint refers to;
Your name, address, telephone number and email address; and
A statement by you: (a) that you believe in good faith that the use of the content that you claim to infringe
your copyright is not authorized by law, or by the copyright owner or such owner’s agent; (b) that all of the
information contained in your Infringement Notice is accurate, and (c) under penalty of perjury, that you are
either the copyright owner or a person authorized to act on their behalf.